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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network116.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
116.0.0.0
Broadcast address
117.255.255.255
First usable
116.0.0.1
Last usable
117.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 74000000 · Integer 1946157056 to 1979711487
Reverse DNS zones
116.in-addr.arpa
117.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110100.00000000.00000000.00000000116.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01110100.00000000.00000000.00000000116.0.0.0
Broadcast01110101.11111111.11111111.11111111117.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

116.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.0.0.0/15116.0.0.1 to 116.1.255.254116.1.255.255131,070
2116.2.0.0/15116.2.0.1 to 116.3.255.254116.3.255.255131,070
3116.4.0.0/15116.4.0.1 to 116.5.255.254116.5.255.255131,070
4116.6.0.0/15116.6.0.1 to 116.7.255.254116.7.255.255131,070
5116.8.0.0/15116.8.0.1 to 116.9.255.254116.9.255.255131,070
6116.10.0.0/15116.10.0.1 to 116.11.255.254116.11.255.255131,070
7116.12.0.0/15116.12.0.1 to 116.13.255.254116.13.255.255131,070
8116.14.0.0/15116.14.0.1 to 116.15.255.254116.15.255.255131,070
9116.16.0.0/15116.16.0.1 to 116.17.255.254116.17.255.255131,070
10116.18.0.0/15116.18.0.1 to 116.19.255.254116.19.255.255131,070
11116.20.0.0/15116.20.0.1 to 116.21.255.254116.21.255.255131,070
12116.22.0.0/15116.22.0.1 to 116.23.255.254116.23.255.255131,070
13116.24.0.0/15116.24.0.1 to 116.25.255.254116.25.255.255131,070
14116.26.0.0/15116.26.0.1 to 116.27.255.254116.27.255.255131,070
15116.28.0.0/15116.28.0.1 to 116.29.255.254116.29.255.255131,070
16116.30.0.0/15116.30.0.1 to 116.31.255.254116.31.255.255131,070
17116.32.0.0/15116.32.0.1 to 116.33.255.254116.33.255.255131,070
18116.34.0.0/15116.34.0.1 to 116.35.255.254116.35.255.255131,070
19116.36.0.0/15116.36.0.1 to 116.37.255.254116.37.255.255131,070
20116.38.0.0/15116.38.0.1 to 116.39.255.254116.39.255.255131,070
21116.40.0.0/15116.40.0.1 to 116.41.255.254116.41.255.255131,070
22116.42.0.0/15116.42.0.1 to 116.43.255.254116.43.255.255131,070
23116.44.0.0/15116.44.0.1 to 116.45.255.254116.45.255.255131,070
24116.46.0.0/15116.46.0.1 to 116.47.255.254116.47.255.255131,070
25116.48.0.0/15116.48.0.1 to 116.49.255.254116.49.255.255131,070
26116.50.0.0/15116.50.0.1 to 116.51.255.254116.51.255.255131,070
27116.52.0.0/15116.52.0.1 to 116.53.255.254116.53.255.255131,070
28116.54.0.0/15116.54.0.1 to 116.55.255.254116.55.255.255131,070
29116.56.0.0/15116.56.0.1 to 116.57.255.254116.57.255.255131,070
30116.58.0.0/15116.58.0.1 to 116.59.255.254116.59.255.255131,070
31116.60.0.0/15116.60.0.1 to 116.61.255.254116.61.255.255131,070
32116.62.0.0/15116.62.0.1 to 116.63.255.254116.63.255.255131,070
33116.64.0.0/15116.64.0.1 to 116.65.255.254116.65.255.255131,070
34116.66.0.0/15116.66.0.1 to 116.67.255.254116.67.255.255131,070
35116.68.0.0/15116.68.0.1 to 116.69.255.254116.69.255.255131,070
36116.70.0.0/15116.70.0.1 to 116.71.255.254116.71.255.255131,070
37116.72.0.0/15116.72.0.1 to 116.73.255.254116.73.255.255131,070
38116.74.0.0/15116.74.0.1 to 116.75.255.254116.75.255.255131,070
39116.76.0.0/15116.76.0.1 to 116.77.255.254116.77.255.255131,070
40116.78.0.0/15116.78.0.1 to 116.79.255.254116.79.255.255131,070
41116.80.0.0/15116.80.0.1 to 116.81.255.254116.81.255.255131,070
42116.82.0.0/15116.82.0.1 to 116.83.255.254116.83.255.255131,070
43116.84.0.0/15116.84.0.1 to 116.85.255.254116.85.255.255131,070
44116.86.0.0/15116.86.0.1 to 116.87.255.254116.87.255.255131,070
45116.88.0.0/15116.88.0.1 to 116.89.255.254116.89.255.255131,070
46116.90.0.0/15116.90.0.1 to 116.91.255.254116.91.255.255131,070
47116.92.0.0/15116.92.0.1 to 116.93.255.254116.93.255.255131,070
48116.94.0.0/15116.94.0.1 to 116.95.255.254116.95.255.255131,070
49116.96.0.0/15116.96.0.1 to 116.97.255.254116.97.255.255131,070
50116.98.0.0/15116.98.0.1 to 116.99.255.254116.99.255.255131,070
51116.100.0.0/15116.100.0.1 to 116.101.255.254116.101.255.255131,070
52116.102.0.0/15116.102.0.1 to 116.103.255.254116.103.255.255131,070
53116.104.0.0/15116.104.0.1 to 116.105.255.254116.105.255.255131,070
54116.106.0.0/15116.106.0.1 to 116.107.255.254116.107.255.255131,070
55116.108.0.0/15116.108.0.1 to 116.109.255.254116.109.255.255131,070
56116.110.0.0/15116.110.0.1 to 116.111.255.254116.111.255.255131,070
57116.112.0.0/15116.112.0.1 to 116.113.255.254116.113.255.255131,070
58116.114.0.0/15116.114.0.1 to 116.115.255.254116.115.255.255131,070
59116.116.0.0/15116.116.0.1 to 116.117.255.254116.117.255.255131,070
60116.118.0.0/15116.118.0.1 to 116.119.255.254116.119.255.255131,070
61116.120.0.0/15116.120.0.1 to 116.121.255.254116.121.255.255131,070
62116.122.0.0/15116.122.0.1 to 116.123.255.254116.123.255.255131,070
63116.124.0.0/15116.124.0.1 to 116.125.255.254116.125.255.255131,070
64116.126.0.0/15116.126.0.1 to 116.127.255.254116.127.255.255131,070
65116.128.0.0/15116.128.0.1 to 116.129.255.254116.129.255.255131,070
66116.130.0.0/15116.130.0.1 to 116.131.255.254116.131.255.255131,070
67116.132.0.0/15116.132.0.1 to 116.133.255.254116.133.255.255131,070
68116.134.0.0/15116.134.0.1 to 116.135.255.254116.135.255.255131,070
69116.136.0.0/15116.136.0.1 to 116.137.255.254116.137.255.255131,070
70116.138.0.0/15116.138.0.1 to 116.139.255.254116.139.255.255131,070
71116.140.0.0/15116.140.0.1 to 116.141.255.254116.141.255.255131,070
72116.142.0.0/15116.142.0.1 to 116.143.255.254116.143.255.255131,070
73116.144.0.0/15116.144.0.1 to 116.145.255.254116.145.255.255131,070
74116.146.0.0/15116.146.0.1 to 116.147.255.254116.147.255.255131,070
75116.148.0.0/15116.148.0.1 to 116.149.255.254116.149.255.255131,070
76116.150.0.0/15116.150.0.1 to 116.151.255.254116.151.255.255131,070
77116.152.0.0/15116.152.0.1 to 116.153.255.254116.153.255.255131,070
78116.154.0.0/15116.154.0.1 to 116.155.255.254116.155.255.255131,070
79116.156.0.0/15116.156.0.1 to 116.157.255.254116.157.255.255131,070
80116.158.0.0/15116.158.0.1 to 116.159.255.254116.159.255.255131,070
81116.160.0.0/15116.160.0.1 to 116.161.255.254116.161.255.255131,070
82116.162.0.0/15116.162.0.1 to 116.163.255.254116.163.255.255131,070
83116.164.0.0/15116.164.0.1 to 116.165.255.254116.165.255.255131,070
84116.166.0.0/15116.166.0.1 to 116.167.255.254116.167.255.255131,070
85116.168.0.0/15116.168.0.1 to 116.169.255.254116.169.255.255131,070
86116.170.0.0/15116.170.0.1 to 116.171.255.254116.171.255.255131,070
87116.172.0.0/15116.172.0.1 to 116.173.255.254116.173.255.255131,070
88116.174.0.0/15116.174.0.1 to 116.175.255.254116.175.255.255131,070
89116.176.0.0/15116.176.0.1 to 116.177.255.254116.177.255.255131,070
90116.178.0.0/15116.178.0.1 to 116.179.255.254116.179.255.255131,070
91116.180.0.0/15116.180.0.1 to 116.181.255.254116.181.255.255131,070
92116.182.0.0/15116.182.0.1 to 116.183.255.254116.183.255.255131,070
93116.184.0.0/15116.184.0.1 to 116.185.255.254116.185.255.255131,070
94116.186.0.0/15116.186.0.1 to 116.187.255.254116.187.255.255131,070
95116.188.0.0/15116.188.0.1 to 116.189.255.254116.189.255.255131,070
96116.190.0.0/15116.190.0.1 to 116.191.255.254116.191.255.255131,070
97116.192.0.0/15116.192.0.1 to 116.193.255.254116.193.255.255131,070
98116.194.0.0/15116.194.0.1 to 116.195.255.254116.195.255.255131,070
99116.196.0.0/15116.196.0.1 to 116.197.255.254116.197.255.255131,070
100116.198.0.0/15116.198.0.1 to 116.199.255.254116.199.255.255131,070
101116.200.0.0/15116.200.0.1 to 116.201.255.254116.201.255.255131,070
102116.202.0.0/15116.202.0.1 to 116.203.255.254116.203.255.255131,070
103116.204.0.0/15116.204.0.1 to 116.205.255.254116.205.255.255131,070
104116.206.0.0/15116.206.0.1 to 116.207.255.254116.207.255.255131,070
105116.208.0.0/15116.208.0.1 to 116.209.255.254116.209.255.255131,070
106116.210.0.0/15116.210.0.1 to 116.211.255.254116.211.255.255131,070
107116.212.0.0/15116.212.0.1 to 116.213.255.254116.213.255.255131,070
108116.214.0.0/15116.214.0.1 to 116.215.255.254116.215.255.255131,070
109116.216.0.0/15116.216.0.1 to 116.217.255.254116.217.255.255131,070
110116.218.0.0/15116.218.0.1 to 116.219.255.254116.219.255.255131,070
111116.220.0.0/15116.220.0.1 to 116.221.255.254116.221.255.255131,070
112116.222.0.0/15116.222.0.1 to 116.223.255.254116.223.255.255131,070
113116.224.0.0/15116.224.0.1 to 116.225.255.254116.225.255.255131,070
114116.226.0.0/15116.226.0.1 to 116.227.255.254116.227.255.255131,070
115116.228.0.0/15116.228.0.1 to 116.229.255.254116.229.255.255131,070
116116.230.0.0/15116.230.0.1 to 116.231.255.254116.231.255.255131,070
117116.232.0.0/15116.232.0.1 to 116.233.255.254116.233.255.255131,070
118116.234.0.0/15116.234.0.1 to 116.235.255.254116.235.255.255131,070
119116.236.0.0/15116.236.0.1 to 116.237.255.254116.237.255.255131,070
120116.238.0.0/15116.238.0.1 to 116.239.255.254116.239.255.255131,070
121116.240.0.0/15116.240.0.1 to 116.241.255.254116.241.255.255131,070
122116.242.0.0/15116.242.0.1 to 116.243.255.254116.243.255.255131,070
123116.244.0.0/15116.244.0.1 to 116.245.255.254116.245.255.255131,070
124116.246.0.0/15116.246.0.1 to 116.247.255.254116.247.255.255131,070
125116.248.0.0/15116.248.0.1 to 116.249.255.254116.249.255.255131,070
126116.250.0.0/15116.250.0.1 to 116.251.255.254116.251.255.255131,070
127116.252.0.0/15116.252.0.1 to 116.253.255.254116.253.255.255131,070
128116.254.0.0/15116.254.0.1 to 116.255.255.254116.255.255.255131,070
129117.0.0.0/15117.0.0.1 to 117.1.255.254117.1.255.255131,070
130117.2.0.0/15117.2.0.1 to 117.3.255.254117.3.255.255131,070
131117.4.0.0/15117.4.0.1 to 117.5.255.254117.5.255.255131,070
132117.6.0.0/15117.6.0.1 to 117.7.255.254117.7.255.255131,070
133117.8.0.0/15117.8.0.1 to 117.9.255.254117.9.255.255131,070
134117.10.0.0/15117.10.0.1 to 117.11.255.254117.11.255.255131,070
135117.12.0.0/15117.12.0.1 to 117.13.255.254117.13.255.255131,070
136117.14.0.0/15117.14.0.1 to 117.15.255.254117.15.255.255131,070
137117.16.0.0/15117.16.0.1 to 117.17.255.254117.17.255.255131,070
138117.18.0.0/15117.18.0.1 to 117.19.255.254117.19.255.255131,070
139117.20.0.0/15117.20.0.1 to 117.21.255.254117.21.255.255131,070
140117.22.0.0/15117.22.0.1 to 117.23.255.254117.23.255.255131,070
141117.24.0.0/15117.24.0.1 to 117.25.255.254117.25.255.255131,070
142117.26.0.0/15117.26.0.1 to 117.27.255.254117.27.255.255131,070
143117.28.0.0/15117.28.0.1 to 117.29.255.254117.29.255.255131,070
144117.30.0.0/15117.30.0.1 to 117.31.255.254117.31.255.255131,070
145117.32.0.0/15117.32.0.1 to 117.33.255.254117.33.255.255131,070
146117.34.0.0/15117.34.0.1 to 117.35.255.254117.35.255.255131,070
147117.36.0.0/15117.36.0.1 to 117.37.255.254117.37.255.255131,070
148117.38.0.0/15117.38.0.1 to 117.39.255.254117.39.255.255131,070
149117.40.0.0/15117.40.0.1 to 117.41.255.254117.41.255.255131,070
150117.42.0.0/15117.42.0.1 to 117.43.255.254117.43.255.255131,070
151117.44.0.0/15117.44.0.1 to 117.45.255.254117.45.255.255131,070
152117.46.0.0/15117.46.0.1 to 117.47.255.254117.47.255.255131,070
153117.48.0.0/15117.48.0.1 to 117.49.255.254117.49.255.255131,070
154117.50.0.0/15117.50.0.1 to 117.51.255.254117.51.255.255131,070
155117.52.0.0/15117.52.0.1 to 117.53.255.254117.53.255.255131,070
156117.54.0.0/15117.54.0.1 to 117.55.255.254117.55.255.255131,070
157117.56.0.0/15117.56.0.1 to 117.57.255.254117.57.255.255131,070
158117.58.0.0/15117.58.0.1 to 117.59.255.254117.59.255.255131,070
159117.60.0.0/15117.60.0.1 to 117.61.255.254117.61.255.255131,070
160117.62.0.0/15117.62.0.1 to 117.63.255.254117.63.255.255131,070
161117.64.0.0/15117.64.0.1 to 117.65.255.254117.65.255.255131,070
162117.66.0.0/15117.66.0.1 to 117.67.255.254117.67.255.255131,070
163117.68.0.0/15117.68.0.1 to 117.69.255.254117.69.255.255131,070
164117.70.0.0/15117.70.0.1 to 117.71.255.254117.71.255.255131,070
165117.72.0.0/15117.72.0.1 to 117.73.255.254117.73.255.255131,070
166117.74.0.0/15117.74.0.1 to 117.75.255.254117.75.255.255131,070
167117.76.0.0/15117.76.0.1 to 117.77.255.254117.77.255.255131,070
168117.78.0.0/15117.78.0.1 to 117.79.255.254117.79.255.255131,070
169117.80.0.0/15117.80.0.1 to 117.81.255.254117.81.255.255131,070
170117.82.0.0/15117.82.0.1 to 117.83.255.254117.83.255.255131,070
171117.84.0.0/15117.84.0.1 to 117.85.255.254117.85.255.255131,070
172117.86.0.0/15117.86.0.1 to 117.87.255.254117.87.255.255131,070
173117.88.0.0/15117.88.0.1 to 117.89.255.254117.89.255.255131,070
174117.90.0.0/15117.90.0.1 to 117.91.255.254117.91.255.255131,070
175117.92.0.0/15117.92.0.1 to 117.93.255.254117.93.255.255131,070
176117.94.0.0/15117.94.0.1 to 117.95.255.254117.95.255.255131,070
177117.96.0.0/15117.96.0.1 to 117.97.255.254117.97.255.255131,070
178117.98.0.0/15117.98.0.1 to 117.99.255.254117.99.255.255131,070
179117.100.0.0/15117.100.0.1 to 117.101.255.254117.101.255.255131,070
180117.102.0.0/15117.102.0.1 to 117.103.255.254117.103.255.255131,070
181117.104.0.0/15117.104.0.1 to 117.105.255.254117.105.255.255131,070
182117.106.0.0/15117.106.0.1 to 117.107.255.254117.107.255.255131,070
183117.108.0.0/15117.108.0.1 to 117.109.255.254117.109.255.255131,070
184117.110.0.0/15117.110.0.1 to 117.111.255.254117.111.255.255131,070
185117.112.0.0/15117.112.0.1 to 117.113.255.254117.113.255.255131,070
186117.114.0.0/15117.114.0.1 to 117.115.255.254117.115.255.255131,070
187117.116.0.0/15117.116.0.1 to 117.117.255.254117.117.255.255131,070
188117.118.0.0/15117.118.0.1 to 117.119.255.254117.119.255.255131,070
189117.120.0.0/15117.120.0.1 to 117.121.255.254117.121.255.255131,070
190117.122.0.0/15117.122.0.1 to 117.123.255.254117.123.255.255131,070
191117.124.0.0/15117.124.0.1 to 117.125.255.254117.125.255.255131,070
192117.126.0.0/15117.126.0.1 to 117.127.255.254117.127.255.255131,070
193117.128.0.0/15117.128.0.1 to 117.129.255.254117.129.255.255131,070
194117.130.0.0/15117.130.0.1 to 117.131.255.254117.131.255.255131,070
195117.132.0.0/15117.132.0.1 to 117.133.255.254117.133.255.255131,070
196117.134.0.0/15117.134.0.1 to 117.135.255.254117.135.255.255131,070
197117.136.0.0/15117.136.0.1 to 117.137.255.254117.137.255.255131,070
198117.138.0.0/15117.138.0.1 to 117.139.255.254117.139.255.255131,070
199117.140.0.0/15117.140.0.1 to 117.141.255.254117.141.255.255131,070
200117.142.0.0/15117.142.0.1 to 117.143.255.254117.143.255.255131,070
201117.144.0.0/15117.144.0.1 to 117.145.255.254117.145.255.255131,070
202117.146.0.0/15117.146.0.1 to 117.147.255.254117.147.255.255131,070
203117.148.0.0/15117.148.0.1 to 117.149.255.254117.149.255.255131,070
204117.150.0.0/15117.150.0.1 to 117.151.255.254117.151.255.255131,070
205117.152.0.0/15117.152.0.1 to 117.153.255.254117.153.255.255131,070
206117.154.0.0/15117.154.0.1 to 117.155.255.254117.155.255.255131,070
207117.156.0.0/15117.156.0.1 to 117.157.255.254117.157.255.255131,070
208117.158.0.0/15117.158.0.1 to 117.159.255.254117.159.255.255131,070
209117.160.0.0/15117.160.0.1 to 117.161.255.254117.161.255.255131,070
210117.162.0.0/15117.162.0.1 to 117.163.255.254117.163.255.255131,070
211117.164.0.0/15117.164.0.1 to 117.165.255.254117.165.255.255131,070
212117.166.0.0/15117.166.0.1 to 117.167.255.254117.167.255.255131,070
213117.168.0.0/15117.168.0.1 to 117.169.255.254117.169.255.255131,070
214117.170.0.0/15117.170.0.1 to 117.171.255.254117.171.255.255131,070
215117.172.0.0/15117.172.0.1 to 117.173.255.254117.173.255.255131,070
216117.174.0.0/15117.174.0.1 to 117.175.255.254117.175.255.255131,070
217117.176.0.0/15117.176.0.1 to 117.177.255.254117.177.255.255131,070
218117.178.0.0/15117.178.0.1 to 117.179.255.254117.179.255.255131,070
219117.180.0.0/15117.180.0.1 to 117.181.255.254117.181.255.255131,070
220117.182.0.0/15117.182.0.1 to 117.183.255.254117.183.255.255131,070
221117.184.0.0/15117.184.0.1 to 117.185.255.254117.185.255.255131,070
222117.186.0.0/15117.186.0.1 to 117.187.255.254117.187.255.255131,070
223117.188.0.0/15117.188.0.1 to 117.189.255.254117.189.255.255131,070
224117.190.0.0/15117.190.0.1 to 117.191.255.254117.191.255.255131,070
225117.192.0.0/15117.192.0.1 to 117.193.255.254117.193.255.255131,070
226117.194.0.0/15117.194.0.1 to 117.195.255.254117.195.255.255131,070
227117.196.0.0/15117.196.0.1 to 117.197.255.254117.197.255.255131,070
228117.198.0.0/15117.198.0.1 to 117.199.255.254117.199.255.255131,070
229117.200.0.0/15117.200.0.1 to 117.201.255.254117.201.255.255131,070
230117.202.0.0/15117.202.0.1 to 117.203.255.254117.203.255.255131,070
231117.204.0.0/15117.204.0.1 to 117.205.255.254117.205.255.255131,070
232117.206.0.0/15117.206.0.1 to 117.207.255.254117.207.255.255131,070
233117.208.0.0/15117.208.0.1 to 117.209.255.254117.209.255.255131,070
234117.210.0.0/15117.210.0.1 to 117.211.255.254117.211.255.255131,070
235117.212.0.0/15117.212.0.1 to 117.213.255.254117.213.255.255131,070
236117.214.0.0/15117.214.0.1 to 117.215.255.254117.215.255.255131,070
237117.216.0.0/15117.216.0.1 to 117.217.255.254117.217.255.255131,070
238117.218.0.0/15117.218.0.1 to 117.219.255.254117.219.255.255131,070
239117.220.0.0/15117.220.0.1 to 117.221.255.254117.221.255.255131,070
240117.222.0.0/15117.222.0.1 to 117.223.255.254117.223.255.255131,070
241117.224.0.0/15117.224.0.1 to 117.225.255.254117.225.255.255131,070
242117.226.0.0/15117.226.0.1 to 117.227.255.254117.227.255.255131,070
243117.228.0.0/15117.228.0.1 to 117.229.255.254117.229.255.255131,070
244117.230.0.0/15117.230.0.1 to 117.231.255.254117.231.255.255131,070
245117.232.0.0/15117.232.0.1 to 117.233.255.254117.233.255.255131,070
246117.234.0.0/15117.234.0.1 to 117.235.255.254117.235.255.255131,070
247117.236.0.0/15117.236.0.1 to 117.237.255.254117.237.255.255131,070
248117.238.0.0/15117.238.0.1 to 117.239.255.254117.239.255.255131,070
249117.240.0.0/15117.240.0.1 to 117.241.255.254117.241.255.255131,070
250117.242.0.0/15117.242.0.1 to 117.243.255.254117.243.255.255131,070
251117.244.0.0/15117.244.0.1 to 117.245.255.254117.245.255.255131,070
252117.246.0.0/15117.246.0.1 to 117.247.255.254117.247.255.255131,070
253117.248.0.0/15117.248.0.1 to 117.249.255.254117.249.255.255131,070
254117.250.0.0/15117.250.0.1 to 117.251.255.254117.251.255.255131,070
255117.252.0.0/15117.252.0.1 to 117.253.255.254117.253.255.255131,070
256117.254.0.0/15117.254.0.1 to 117.255.255.254117.255.255.255131,070

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.